1. Field of the Invention
The present invention relates to power supplies. More specifically, the present invention relates to methods and apparatus for an electronic power supply for use with a personal computer and including an external power section located exterior to the personal computer and an internal power section located interior to the personal computer, wherein both the external power section and the internal power section each include a separate supervisory computer for controlling the electronic power supply to provide optimal performance and fault correction.
2. Description of the Prior Art
The prior art is directed to methods and apparatus for power supplies used in personal computers.
The personal computer and other computing devices require an input of electrical power for energizing circuitry within the computer. Typically, the electrical input is derived from an alternating current (AC) voltage source typically referred to as house power. However, most computers require multiple direct current (DC) voltage levels to provide adequate power thereto. That portion of the computer that accepts the AC voltage input signal and performs a conversion to provide one or more DC voltage levels required for operation of the computer is known as a power supply.
Typically, prior art power supplies for personal computers include an AC voltage input signal which is applied to the primary winding of a stepdown transformer after a power switch has been actuated. The transformer typically steps-down the input AC voltage signal such as, for example, 110 VAC, single phase, 60 Hz, to provide a low voltage AC signal at the secondary winding of the transformer. The stepped-down AC voltage signal is then applied to a rectifier circuit typically comprised of a plurality of solid state diodes for converting the AC voltage at the secondary side of the transformer to a DC signal. The DC voltage signal is then applied to a capacitive filter device for smoothing the ripple in the rectified DC signal. The filtered DC signal is then further manipulated to provide one or more voltage signals at different DC voltages for use within the personal computer. Additionally, the power supply usually also includes an on-board back-up battery source and charger for providing the necessary DC voltages signals to enable operation of the personal computer during loss of AC power or when an AC source is unavailable.
The conventional device described hereinabove comprises a single power supply housed within the same cabinet as the personal computer. Certain components located within the power supply, i.e., step-down transformer, rectifier circuit, battery, battery charger and the like, are heat generating components. Thus, a problem that exists within prior art power supplies is that the heat generated by these components causes the temperature within the personal computer cabinet to increase. The increased temperature environment within the personal computer results in degraded performance and a shorted life cycle of the components within the electronic circuitry. Further, the high temperature environment necessitates the inclusion of an adequately sized cooling fan. Manufacturers of specific types of personal computers such as, for example, xe2x80x9cLaptopsxe2x80x9d, have located the stepdown transformer of the power supply within a sealed non-conductive block remote from the personal computer cabinet. However, the remaining heat generating components continue to be positioned within the personal computer cabinet.
Other problems also exist with conventional power supplies intended for use with personal computers. Typically, each manufacturer of personal computers and other computing devices tailors the design of their power supply to one specific type or model of personal computer. Thus, the power supply of any particular manufacturer of personal computers is not useful as a power supply in the personal computer of any other manufacturer. The reason is that the criteria used to design the power supply for one personal computer (i.e., voltage outputs, current levels, dimensions, weight and the like) typically will not be the same as the criteria used to design the power supply for a personal computer of another manufacturer. Thus, different power supplies designed by different manufacturers for use in personal computers are not universally useful. Another problem with conventional power supplies for use in personal computers is that they consume too much space within the personal computer. This creates a problem in an era where the emphasis is on smaller packaging of all electronic devices. An additional problem is that the signal waveforms of the input AC voltage signal become distorted as the power demand increases such as, for example, at half-load. The signal waveform distortion is even more pronounced when the power demand is at full-load. The waveform distortion caused by conventional power supplies is undesirable since it affects the waveform and performance of other electrical loads such as electrical lighting and other computer peripherals.
Thus, there is a need in the art for an electronic power supply for use with a personal computer that exhibits a design comprising an external power section and an internal power section, each of which is controlled by a supervisory computer for ensuring optimal performance, fault correction and substantial heat load reduction resulting in extended life and improved performance of electronic components, occupies less space, provides improved cooling within the personal computer cabinet, reduces the distortion of the signal waveforms of the input AC voltage when the power supply is under load, and can be employed to universally replace the singular heat generating, internal power supply of most models of personal computers.
Briefly, and in general terms, the present invention provides a new and improved electronic power supply and method therefore which is typically employed in a personal computer or other computing device for providing multiple regulated direct current (DC) voltages required by modern personal computers. Generally, the electronic power supply for use with a personal computer is comprised of an external power section located exterior to the personal computer and an internal power section located interior to the personal computer. The external power section includes the power generating (and heat generating) components while the interior power section includes the power distributing components of the electronic power supply.
In a preferred embodiment, the external power section of the electronic power supply for use with a personal computer includes a stepdown transformer, a rectifier circuit, a stand-by battery and charging circuit, a cooling fan, various instruments for monitoring system parameters and a first supervisory computer for controlling and optimizing the efficiency of the electronic power supply. A rectified DC voltage is augmented by the stand-by battery to provide an uninterruptible power source limited by the storage capacity of the stand-by battery. The augmenting of the rectified DC voltage with the stand-by battery results in minimized waveform distortion typically occurring in prior art power supplies. The resultant rectified DC voltage is then cabled from the external power section to the internal power section. The isolation of the external power section away from the personal computer removes many of the heat generating components from the computer resulting in lower operating temperatures. Consequently, the life of internal electronic components is extended enabling upgrades to higher speed processors.
The internal power section of the electronic power supply includes a plurality of high efficiency, solid state DC-to-DC buck switching converters and polarity-reversing inverters to provide individually regulated voltages required by the personal computer. The DC-to-DC buck switching converters lower and regulate individual voltages from a single DC voltage provided by the external power section of the electronic power supply. The internal power section also includes a second supervisory computer for controlling and optimizing performance and correction of faults sensed by a plurality of instruments for monitoring system parameters. Most of the power (and heat) generating components have been removed to the external power section and the high efficiency, solid state DC-to-DC buck switching converters and polarity-reversing inverters produce very little heat. Therefore, the internal power section of the electronic power supply operates in a much cooler environment compared to conventional power supplies.
The present invention is generally directed to a power supply and particularly directed to a power supply for use with a personal computer. Use of a pair of supervisory computers for controlling the external power section and the internal power section enables temperature, load-sharing, current sensing, and other monitoring/control functions to optimize the efficiency of the electronic power supply. Any of the parameter monitoring devices in either section is capable of providing an alarm signal to the first supervisory computer for interrupting the DC power provided by the external power section. The interruption of the DC power occurs by tripping, i.e., opening, a power control relay located in the external power section. The power control relay can also be opened by a signal transmitted on a communication line from the second supervisory computer in the internal power section. A Universal Serial Buss (USB) interface enables the personal computer to monitor/display fault conditions as they occur.
In its most fundamental embodiment, the electronic power supply for use with a personal computer exhibits a construction including an external power section located exterior to a personal computer and including a direct current voltage source in combination with a battery source for providing a load adjusted direct current source. A first supervisory computer is connected to the direct current voltage source and the battery source for controlling the load adjusted direct current voltage. An internal power section is located interior to the personal computer and in electrical contact with the external power section. The internal power section comprises a plurality of voltage output devices for providing a plurality of direct current output voltages. A second supervisory computer is connected to the plurality of voltage output devices for controlling the plurality of direct current output voltages distributed to the personal computer. A signal communication link exists between the second supervisory computer and the first supervisory computer.
These and other objects and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings which illustrate the invention, by way of example.